title: Preparation and characterization of pH-responsive guar gum microspheres.
abstract: Guar gum, being the natural polymer is renewable, nontoxic, biocompatible and biodegradable. Therefore, it is the perfect material to formulate particulates or microspheres for potential applications in pharmaceutical. The formulation of material in nano/microsphere scale offers new rich in application potential. In view of that, novel biodegradable and pH-sensitive hydrogels composed of pH-sensitive methacrylic acid (MAc) and a biodegradable guar gum were synthesized by grafting reactions. Water-in-oil (w/o) emulsion method was used to direct the pH-sensitive material in microspheres shape using bi-functional glutaraldehyde (GA) as crosslinker. The synthesized microspheres were characterized by FTIR and SEM (different magnification). The swelling ratios of hydrogels in buffer solutions showed a pH-dependent profile at physiological pH. In vitro release data was analyzed using Fick's law, which indicated swelling controlled super case II transport of BSA through the synthesized microspheres. Therefore, in conclusion, as ascertained from the results the introduction of -COOH moieties along the guar gum chain drastically increases the end-use performance due to pH-sensitivity.
authors.affiliation: School of Chemistry, Shoolini University, Solan 173229, India.
authors.forename: Shitika
authors.initials: S
authors.lastname: Sharma
authors.forename: Jasvinder
authors.initials: J
authors.lastname: Kaur
authors.forename: Gaurav
authors.initials: G
authors.lastname: Sharma
authors.forename: Kamal Kishor
authors.initials: KK
authors.lastname: Thakur
authors.forename: Ghanshyam S
authors.initials: GS
authors.lastname: Chauhan
authors.forename: Kalpana
authors.initials: K
authors.lastname: Chauhan
mesh_terms: D003432:Cross-Linking Reagents; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods; D005685:Galactans / Q000737:chemistry* / Q000648:ultrastructure; D005976:Glutaral; D020100:Hydrogels; D006863:Hydrogen-Ion Concentration; D008351:Mannans / Q000737:chemistry* / Q000648:ultrastructure; D008689:Methacrylates / Q000737:chemistry; D008863:Microspheres; D015394:Molecular Structure; D053149:Plant Gums / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D003432:Cross-Linking Reagents; D004337:Drug Carriers; D005685:Galactans; D020100:Hydrogels; D008351:Mannans; D008689:Methacrylates; D053149:Plant Gums; C008384:methacrylic acid; C007894:guar gum; D005976:Glutaral
keywords: Emulsion polymerization; Microspheres; pH-sensitive